Herein, we describe the generation of an organochromium-type carbanion species from a non-activated C–H bond and its nucleophilic addition to aldehydes. The catalytic carbanion generation occurred through formal deprotonation of a non-activated C–H bond under mild conditions and did not need the prefunctionalization or anion stabilizing group. Carbon radical intermediates generated by decatungstate photocatalyst-mediated hydrogen abstraction were captured by a chromium salt with the reductive radical-polar crossover reaction to produce organochromium carbanions.

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Direct nucleophilic substitution of alcohols with thiols or carbon nucleophiles was achieved using a mesoporous silica-supported oxovanadium catalyst (VMPS4). Benzyl and allyl alcohols were compatible in this reaction under mild conditions, affording the products in high yields. The VMPS4 catalyst showed excellent chemoselectivity toward alcohols in the presence of acid-labile functional groups, which is in contrast to that observed for the commonly used Lewis acid catalysts, which exhibit poor selectivity. The VMPS4 catalyst could be recycled by simple centrifugation, and the catalytic activity was maintained over seven cycles.

The Cover Feature shows the chemoselective, direct nucleophilic substitution of alcohols. An alcohol and an ester are competing in the Tokyo Olympics steeplechase passing through the Olympic symbol, representing a mesoporous silica‐immobilized oxovanadium catalyst, developed in our group. The alcohol is now on the verge of winning the race, i.e. the direct nucleophilic substitution with a sulfur or carbon nucleophile, accompanied by generation of a molecule of water as the only by‐product. More information can be found in the Full Paper by S. Akai et al.

Ketones are a fundamental functionality found throughout a range of natural and synthetic compounds, making their synthesis essential throughout the chemical disciplines. Herein, we describe a one-pot synthesis of ketones via decatungstate-mediated formal dehydrogenative coupling between aldehydes and non-activated hydrocarbons. A variety of substituted benzaldehydes and cycloalkanes could be used in the optimized reaction to produce the desired ketones in moderate yields. The decatungstate photocatalyst functions in two reactions in this synthesis, catalyzing both the coupling and oxidation steps of the process. Notably, the reaction displays both high atom economy and sustainability, as it uses light and oxygen as key energy sources.